1. Field
This application relates to laser smoke evacuation systems used during laser surgical procedures and more specifically to laser smoke evacuation systems with smoke filter obstruction indicators.
2. State of the Art
Laser surgical procedures are widely used for removing excess or diseased tissue. When subjected to the concentrated energy of the laser, the tissue of interest is vaporized into laser smoke. The laser smoke may contain infectious viral or microbial components, and must be evacuated to prevent exposing the surgical staff to these potentially harmful components.
Devices to evacuate laser smoke generated during laser surgery typically employ a motor driven vacuum pump to suction the smoke into the device. The smoke may then be passed through a filter where particulates and potentially harmful materials are removed.
Over time, filtered material clogs the pores of the filter resulting in a change in suction capability and filtering capacity. The filter must then be replaced to maintain a safe environment for the surgical staff. If the filter becomes extensively clogged during surgery, it may be necessary to stop the surgery until the filter can be changed.
Several U.S. patents teach devices to evacuate and filter laser smoke generated during laser surgery. Some of the devices are capable of indicating a clogged filter condition. These devices, however, do not indicate the extent of filter obstruction, or compensate for a change in suction capability as the filter becomes clogged.
It would be useful to know the extent of filter obstruction at all times. A substantially clogged filter could then be replaced before beginning a surgery. It would also be useful if the smoke evacuation system could compensate for a change in suction capability as the filter progressively becomes clogged. Ideally, such a system should be capable of automatically controlling the level of evacuation to correspond with the level of laser smoke production.